After updating my AIX 7.1 TL3 system to service pack 4 , I noticed that each time I started a new ssh session with this system, there was a noticeable delay before the login prompt was displayed. I initially thought there was a network or host name...

We frequently need to confirm connectivity between systems on particular ports. telnet The simplest way to do this is with the telnet command. The syntax is: telnet <server> <port> Failure One kind of failure looks like this: telnet <server>...

Often times you'll find a command line that works perfectly when you run it locally on a server, but doesn't work when you run it remotely over SSH. Usually the problem is related to double quotes, or backticks in the command. In this post,...

Often times System Administrators need to copy a file to remote servers with root authority. One example might be to push out an updated resolv.conf file to all servers. However, often times remote root logins are disabled so it can be...

The latest development versions of PuTTY have a awesome new feature called "Share SSH Connections" (Connection Sharing). I did a video that covers the basics of this feature and shows a demo of it in action: https://www.youtube.com/watch?v=GGYO...

So you have a extensive IBM AIX environment with all of your SSH keys set-up, but now you have built a number of Linux servers which you want to add into this key range. So you copy over the existing authorized_keys file from your AIX system to a Linux host,...

If you aren't familiar with EZH (the Easy HMC Command Line Interface), check out the EZH project website on sourceforge It is a free, easy to install script for your HMC that provides a much better command line interface to...

This will be a problem and won't make your life easy ... So what will happen in this case ? - root can't connect to any compute node without password using ssh (including the installer-failover) - cfmsync will not work Good news, the content of the...

5 Steps to updating OpenSSH on a VIO server I was doing some health checks when I noticed that some of our VIO (2.1.3) servers was running a version of OpenSSH that has a known security vulnerability. You will hopefully be aware that OpenSSH is provided by...

Recent releases of AIX installation media
(for 7.1 and 6.1) now contain the OpenSSH base installation filesets. This is
very handy; we no longer need to download or locate the software from other
sources. One thing to consider is what this means
for...

I love a command line. It's numerous advantages over GUI is hard to list, but there are situations, where you need a remote X Windows connection. I've been asked many times by my colleagues, how to set up remote X Windows (X11, as the most recent version of X...

The first time you connect to a server using SSH you are prompted to accept the host key. After this, each time you connect the client uses the cached SSH host public key (stored in ~/.ssh/known_hosts) to authenticate that the server it is connecting to...

Connecting to remote Linux desktops on is frequently needed in
cloud applications. Because the remote machines are on the Internet
you should be avoid sending unsecured network traffic to them and
also avoid opening insecure services, like VNC, on the...

A little known feature of the bash
shell is process substitution. This essentially allows you to take
commands that normally require files as input and instead provide
them the output of commands as input. One example of this is if you need to
compare...

The Storwize V7000 and SVC have a command line interface that you access via SSH . Every-time you logon, whether it is to transfer a file (using a tool like pscp ), issue a single shot command from a script (using a tool like plink ) or logon to issue...

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For those who use IBM vios or HMC a lot, one might have the need to ssh into some machine running “Restricted Shell” of IBM products, like restricted bash for HMC and ksh for VIOS .
Many times public keys manipulations are needed to make login and...

Secure terminal access to a cloud instance via your phone is easy and fun if you follow this tip, which involves using PuTTY from Windows to access a Linux instance, converting that key to an OpenSSH key, copying the OpenSSH key to Android, and running an SSH...

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